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michael sweet at 20:01 PM on 31 March 2014Honey, I mitigated climate change
Andy,
Certainly how the grid is paid for is the argument that the utilities make. Different people will interpret the arguments differently. Hawaii is a trial run for the USA as solar is currently the cheapest form of electricity there. It will be interesting to learn what type of upgrades are required for neighborhoods to send electricity over existing wires back to the utility. The utility currently claims it cannot be done. The technicalities are complex for people who do not work in the industry.
In my local paper today a report states that the Florida state legislators are in the back pocket of the utilities. That surprises no one in the USA. Perhaps if Australia shows that electricity is much cheaper when people make their own, the US will be dragged along.
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Tom Curtis at 19:29 PM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Sorry, minimum trend for 1984-2013 was 0.114 C/decade, not 0.011 as stated.
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Tom Curtis at 19:26 PM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
klapper @21, 28, & 30, I have downloaded the RCP 4.5 data for all 42 ensemble members from January 1961 to December 2050 from the KNMI Climate Explorer. For the 30 year trend ending December, 2013, the ensemble shows a mean trend of 0.254 C/decade, with a Standard Deviation of 0.059 C/decade. That means any trend lying between 0.136 and 0.372 C/decade lies within the prediction interval of the ensemble. All three major temperature indices plus Cowtan and Way lie within that interval, the trends being:
HadCRUT4: 0.17 +/- 0.053 C/decade (7.1%)
NOAA: 0.162 +/- 0.052 C/decade (4.6%)
GISS: 0.172 +/- 0.056 C/decade (7.6%)
Cowtan and Way (HadCRUT4 Hybrid): 0.193 +/-0.06 C/decade (12.8%)
The numbers in brackets are the percent rank of the indices among the ensemble.
For the record, the Minimum trend in the ensemble is 0.011 C/ decade, and the Median trend is 0.249 C/decade.
Clearly neither ensemble mean prediction, nor the ensemble distribution justify claim that the models are falsified by the temperature record. That is particularly the case as there are several independent reasons to expect the ensemble to over predict the trend from 1984-2013 inclusive. First, for HadCRUT4 and NOA, neither includes the entire globe and consequently both will under predict trends due to failure to represent polar amplification.
More importantly, 1984 is still close enough to the El Chichon volcanoe of 1982 for temperatures to be negatively impacted. In real life, the impact of that volcanoe was largely nullified by the strongest El Nino on record, as measured by the SOI. More generally, that El Nino represents a peak in SOI influence on temperature, which has shown a strong negative trend since then. That has culminated, in 2011 with the strongest La Nina on record:
This strong trend in SOI conditions results in a strong negative trend in temperatures not represented by any forcing, and therefore not a feature of the ensemble mean. This couples with the lower than projected forcings to strongly bias observations relative to the ensemble.
This bias can be removed for practical purposes by comparing all thirty year trends over a period or reasonably constant increases in forcing, such as that from 1961-2050, or if you prefer largely historical values, from 1961-2013. The ensemble mean trends over those periods are, respectively, 0.222 +/- 0.076 C/decade and 0.187 +/- 0.078 C/decade. All four temperature series above lie very comfortably within the prediction interval in both cases, particularly the historical interval. For the historical period, they lie in the 41st, 36th, 42nd, and 56th percentiles respectively in order of appearance on the table above.
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Ari Jokimäki at 15:26 PM on 31 March 2014Honey, I mitigated climate change
Andy: Ari commented in his piece that natural gas replacing coal increases warming in the short ter because of the reduction in aerosols from coal. This observation applies equally to renewables that replace coal, as well.
Of course, except that biomass burning also releases aerosols, but this doesn't take away the fact that this feature is also present when switching from coal to natural gas. The situation of natural gas is somewhat different than the situation with solar or wind energy, because solar and wind energy at least really reduce GHG emissions, so even with aerosol effect, there is a possibility to reduce the warming effect overall. In natural gas case it just amplifies already bad situation.
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Andy Skuce at 14:25 PM on 31 March 2014Honey, I mitigated climate change
Michael @ 39: I would say that it's not just a question of utility profits, but how the grid is paid for and by whom. I would suspect that the solution for this would have to be some kind of fixed grid connection charge independent of the usage, plus some time-variable charges for the electricity. It is probably not that hard to figure out how to do this, but the politics for the regulators are probably very difficult.
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Andy Skuce at 14:17 PM on 31 March 2014Honey, I mitigated climate change
According to Wiki about one-third of US electricity consumption is residential.
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scaddenp at 13:04 PM on 31 March 2014Honey, I mitigated climate change
Actually, MacKay has an interesting 2-pager (and thought-provoking map) on energy options for the US here. Note that the solar options considered are CSP and biomass, not PV. (At time of writing, MacKay thought PV somewhat too expensive to consider). It does give you a feeling for the size of the problem. It would be interesting for someone familiar with the US energy use to comment on options for energy saving. There are anomolies that I cant explain. US electricity consumption alone is around 100 kWh/d/p - more than NZ total energy consumption of 88kWh/d/p. Oil/gas consumption is around 150kWh/d/p - more than 3x NZ usage. Hmm. How much is domestic energy use, how much is industrial use? I can see US consumer being more electricity demanding than a NZer, and that home heating/cooling needs are higher, but surely not by that much. US industrial use would by much higher and if this is where most energy goes, then it's likely to be harder to make energy conservation measures. Because it affects the bottom-line, industries tend to be far more focussed on energy efficiency than a domestic consumers. Anyone done a MacKay type analysis on where the US spends its energy?
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Klapper at 12:26 PM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@scandenp #29:
Best is only land is it not? Note that my calculation on the error in the model trend above uses HadCRUT4 Hybrid with a trend of 0.19C/decade over the last 30 years, which is actually higher than GISS at .172C/decade, which is only slightly higher than HadCRUT4 at .169C/decade. I don't think it will make a lot of difference but I can plot up the rolling trend for all three (NOAA, HadCRUT4 and GISS) against the rolling CMIP5. Or maybe it's best to average the anomalies for all three Global SAT datasets.
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michael sweet at 10:41 AM on 31 March 2014Honey, I mitigated climate change
Ranyl,
What type of power do you support? I see you do not like solar or coal, can you suggest alternatives?
Andy,
The utilities make much of their profits on the peak load period from about 12:00-6:00PM every day. Solar cuts directly into this peak and causes a disproportionate dip in utility profits. In Hawaii this might be 5% of peak power, since solar produces no energy at night. It is difficult for those (like me) who are not professionals to understand all the ins and outs. The bottom line is that utilities do not like wind and solar competing with them during peak profit hours. They did not say much about it until the past year or so because solar and wind were not economic. Now that home solar and xommercial wind are economic the arguments are starting. In progressive areas (like Germany) solar is adopted more quickly. In backwards areas (like Florida, where I live) solar still struggles.
The grid in Hawaii might be able to support more solar, but the utility profits cannot. We will have to wait for several analysis to be done.
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scaddenp at 09:59 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper, given recent papers on issues on HadCrut4, why choose that rather than BEST or GISS?
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scaddenp at 09:55 AM on 31 March 2014Honey, I mitigated climate change
Ranyl, I would be extremely interested then in your opinions on McKay's "Sustainable Energy without the Hot Air". I struggle to figure out how US citizens can use 250kWh/d/p, so I do agree that conservation will make an important role, but looking at his numbers, it is also clear that making meaningful reductions by conservation is going to be tough. I ran the analysis for NZ and figured you could realistically get 25kWh/d/p, with 10 of that from electric vehicles.
If you are going to replace the energy generated from coal, (the main problem), then you really need solar (either PV or CSP, and realistically both) or nuclear. If you think you can do it another way, then please show us your arithmetic.
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One Planet Only Forever at 09:49 AM on 31 March 2014The Carbon Bubble - Unburnable Fossil Fuels - Seminar and Discussion
Andy @3
I view CCS as likely being used as an unsustainable excuse to continue an unsustainable activity that creates far more harm than the production of excess CO2. CSS should be a required added expense for any attempt to continue burning fossil fuels, but only be used for a short transition period, even shorter than the possible life of a new fossil fuel burning facility. The already fortunate people on this planet, particularly the most fortunate, need to be motivated to develop and follow truly sustainable ways of living as rapidly as possible.
The only viable future for humanity is progress to truly sustainable activity by all humans, as part of a robust and diverse web of life on this amazing planet. I have read many things and thought many thoughts, but I have not come up with any plausible way for the consumption of non-renewable resources to have any legitimate role in that sustainable future. In fact, I consider located, but otherwise untouched, fossil fuels to be a potentially critical emergency resource at some point in that future.
If you believe there is a viable way for humanity to enjoy the hundreds of millions of years that it should be possible to enjoy on this amazing planet while consuming non-renewable resources I would love to hear the details of it.
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Stephen Baines at 09:23 AM on 31 March 20142014 SkS Weekly News Roundup #13A
Previous post was addressed to Tom Curtis.
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Klapper at 09:20 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Dayton #25:
"In this case we are concerned with the projections over periods of 30 years or more (the definition of "climate")."
To expand on my comparison of the CMIP5 mean to empirical data, I downloaded six model runs to compare to the last 30 year global SAT warming trend. Keep in mind these models use actuals up until 2000, so the model is not guessing CO2 output or any other input for the first 1/2 of the analysis period. I used rcp45 after looking at some of the emissions projections. Rcp45 has the highest sulphur emissions which given the rapid increase in emissions from China, also seems the most realistic. In any case all rcp scenarios use the same CO2 up until 2005. If there was more than one run (true for most chosen models), I used run 0 since I'm guessing that was the baseline run. The models used were CSIRO-Mk3, GISS-E2-R, GFDL-CM3, GFDL-ESM2M, HadGEM2-ES,and MPI-ESM-LR.
The results show a fairly wide range of projected trends, from a minimum of 0.22C/decade to a maximum of 0.38C/decade, with an average of 0.28C/decade, slightly higher than the CMIP5 ensemble mean of 0.26C/decade. Even using the HadCRUT4 "Hybrid" trend for the last 30 years to compare (0.19C/decade) the average of the model runs looks to have a warming rate that is too high by 40 to 50%, depending on whether you use my selection of 6, or the CMIP5 ensemble.
However, I think the models correlate well with global SAT if you end the 30 year trend analysis period in 2000. The next step is to plot a rolling 30 year trend comparison CMIP5 ensemble vs HadCRUT4 and look for bias in the models relative to major volcanic episodes, ENSO etc.
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jimlj at 09:20 AM on 31 March 2014Honey, I mitigated climate change
Andy, also look at http://kauai.coopwebbuilder.com/ a different Hawaiian utility.
It plans to generate 50 to 60% of electricity from renewable sources by 2025. Also, from http://kauai.coopwebbuilder.com/content/fuel-mix-information they've reduced fossil fuel generation by 6.5% from 2008 to 2012. In addition, the end of 2012 they brought on line a solar array that will supply 3% of the island's power, and in 2013 began construction of an array twice as big, with a third array planned.
Where they are is less important than how fast they are moving, and with Kauai that's pretty fast.
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Stephen Baines at 09:14 AM on 31 March 20142014 SkS Weekly News Roundup #13A
Basically, I agree on both points. I try to use the term "established knowledge" to indicate statements that the community has adjuged can be treated as true based on the evidence. Individual scientists often use these statements as starting points in generating hypotheses or defining questions. They are open to question if enough evidence challenges them - but it has to be A LOT of evidence, as there is already a lot of evidence in support of them. I gave some examples that I think would be very hard to challenge given the current evidence.
In the article that Poster referred to, the basic tenets of AGW were accepted as given. To then imply that, by addressing a set of new questions premised by established knowledge, scientists necessarily undercut the premises upon which the new questions were based is tantamount to saying one cannot do science of any sort. It's extremely sloppy thinking, but I think it is not uncommon thinking.
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ranyl at 09:13 AM on 31 March 2014Honey, I mitigated climate change
"All_ energy sources, coal, solar, nuclear, etc, have side effects - it's a matter of deciding which effects are more problematic. I would strongly argue in the comparison of solar and coal that the advantages of no carbon emissions _hugely_ gives the balance to solar, and I consider your solar objections more quibbling than anything else."
Hmm I never said use coal yet all I get is coal comparisons, and I have said coal isn't not good at all and I would wish we could stop using it all together tomorrow.
And how are electronics and PV recycled, what processes are involved, energy intensive and using multiple chemical processes and etching processes, and where do all the acids come from?
LINK
As for quibbling well no these are real concerns and there are choices to be made, power down as much as possible (quick, effective, easy), wind, hydro, marine or solar. At present solar needs gas to make or another heat source, make that electric and energy use goes up I suspect.
So take coal out of the equation and where does solar PV stack up and very worrying how little weight is put on toxic waste in LCA and the like and most by far published in renewable energy favorable journals by renewable energy research groups, and the Energy return vary from 0.8yr to 12year depending on energy mix and how you mix the figures up mainly, and so little accounting for carbon fluxes due to ecosystem disturbances from mining, toxic waste bits etc....Almost Like it doesn't matter and ignores how ecosystem disruptions tend to lead to carbon releases like shading soil?? (down respiration rates as cooler, but little plant growth so can only respire soil carbon so releases?? all very tricky to know and needs investigating further)
"You are ranting and sloganeering. Provide more citations that support your wild claims and less assertions from ignorance."
Yet I do reference everything I written and in the reference to Hawaii power it states Hawaii Island uses 22% Geothermal which seems a reasonable amount.
I also gave the Nature Climate Change reference about the non displacement of fossil fuels by renewables, I didn't make it up, and due to backup reserve increases when things aren't generating, balancing issues (York hypothesized) and yes when people think they are getting good green electricity they tend to sue more of it cos it good isn't it, so does tend to discourage power down as all feel good no problems electricity. Indeed it is even widely stated it improves the environment. And that is of course false how can a process requiring a multitude of manufacturing processes, lots of toxic substances to make (and they have to be manufactured and sourced also), and lots of heat (supplied by gas mainly at present) improve the environment?
Well only if compared to coal, but again to reiterate I think we shouldn't use coal at all.
"You appear to claim that all energy use must be curtailed. That will never happen. You must provide an alternate scenario for people to live."
Well I never said that, I said to get anywhere near the targets needed to prevent serious global warming a significant power down would be the cheapest, quickest, easiest and totally non environmentally harming way to do it. However that isn't to zero power, but trying to replace all power with renewable is going to costs lots of carbon and create lots of waste in the case of PV.
Is our power addiction worth this risk, I'd rather power down more than use PV and create a waste mountain or energy legacy (to recycle them needs lots of energy) to deal with and it could be a huge waste mountain.
And I wonder how many times they'll be able to be recycled, they only get 95% of the stuff out at present, mainly the glass (by crushing or milling and then heat), silicon by heat of chemical agents)m the toxic waste bits, hard to say what happens to them, but about 5% of something goes to landfill (http://www.pvcycle.org.uk/).
EVA (ethylene vinyl acetate) I wonder what will happen to that? And the other plastics in the PV's and what do they use to clean them in manufacture and what are the various retardants etc made from I wonder?
Therefore lets not compare to coal, as we all agree coal is so bad we shouldn't use it at all.
Then PV is a energy provision technology that requires very high temperatures, rare earth elements, plastics, treated films and membranes, storage technologies, lots of area, mining, lots of strong chemicals to etch and scribe, and then wiring, Inverters and several other aspects all associated with waste, no wonder the UK classified under the electronic waste this year, as PV are now WEEE, and people say there is no waste associated them.
So here are in a real and current environmentally emergency in terms of global warming and biodiversity losses, both of which are direct threats to human existence in themselves and rather than power down and put as little additional GHG into atmosphere and toxic waste into the environment as I would suggest is best approach, I am told to risk lots of additional GHG and create additional toxic waste issues.Moderator Response:[RH] Hot-linked URL. Please try to learn how to embed links instead of posting long URL's (second tab at the top of the comments box). Those long URL's break the page formatting of this website.
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Andy Skuce at 08:34 AM on 31 March 2014Honey, I mitigated climate change
Thanks,Michael. That was very helpful.
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michael sweet at 08:16 AM on 31 March 2014Honey, I mitigated climate change
Andy,
The link Ranyl provided shows electricity generated by the utility. Much solar power is generated by individuals with solar panels on their roofs. This shows up as reduced demand to the utility, not as power generated. According to this Scientific American article, about 2.6% of electricity in Hawaii is generated by solar systems. The utilities have stopped all current instalations of new solar claiming the grid cannot handle the load. They do not allow neighborhoods to return power to the grid during the day, only to shift electricity to nearby houses. The utilities do not want to be put out of business by cheaper power from individuals. There will undoubtedly be arguments about how the grid can be adjusted to accept electricity from individuals. There will likely be arguments for a long time. If solar becomes cheap enough, it will eventually win out.
Hawaii also has issues caused by the very small size of its electricity grids. Each island is a separate grid. This causes balancing issues in the event of a very large cloud coming over a single island.
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Tom Dayton at 07:39 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj, perhaps you think that we expect the actual temperature to fall exactly on the "ensemble mean" hindcast and forecast. But we don't, because that mean has far too little variability. In fact, we expect the temperature to have wild ups and downs as you see exemplified by the orange and blue skinny lines in Figure 2, because we expect there to be El Ninos and La Ninas, variation in solar radiation, volcanic eruptions, changes in human-produced aerosols due to varying economic activity, and a slew of random and semi-random factors. It would be downright shocking if actual temperature followed the ensemble mean, because that would mean all those variations in forcings and feedbacks were far less variable than we have observed so far. So we judge the match of the real temperature to the projected temperature by whether the real temperature falls within the range of the entire set of individual model runs. Even so, we expect the real temperature to fall within that range only most of the time, not all of the time. The range you see drawn as a shaded area around the ensemble mean usually is the 90% or 95% range, meaning the set of individual model runs falls within that shaded range 90% or 95% of the time. That means, by definition, we fully expect the real temperature to fall outside that range 10% or 5% of the time. So occasional excursions of the real temperature outside that range in no way invalidate the models, when "occasional" means 10% or 5% of the time.
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Tom Dayton at 07:26 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj, understandably you might misunderstand what a "hindcast" is. It is produced in the same way as a forecast: The model is started very long ago--far earlier than the first year you are trying to hindcast. The model results gyrate wildly for a while as the simulated years tick by, then settle down. Eventually the model gets around to the first year you are trying to hindcast. The model continues through the years until getting to the year in which the model is being run. As the model continues spitting out results year by year in exactly the same process it has been following since it was started up, the "hindcasts" become "forecasts" only because the years that the models are simulating switch from being earlier than this year to being in the future from this year. For example, if climatologists start running their model on their computer in the year 1998 (I'm guessing that's where the vertical green dashed line in Figure 2 falls), then the model's outputs for each of the simulated years 1960 through 1997 are labeled "hindcasts" and the outputs for the simulated years 1998 and later are labeled "forecasts." Other than that labeling, there are no differences in how the model outputs are produced or reported. There are no adjustments to the model to tune it to actual climate.
What is done on the basis of analyses of model versus past reality is, as Kevin C explained, "improvement" of the fundamental physics of the model. I put "improvement" in quotes, because the modelers try to improve the physics but do not always succeed. They base any such adjustments on fundamental physical evidence, not by simply reducing the influence of an effect because they think it will make the projections better match observations. For example, if the modelers change the modeled reflectivity of clouds, they do so based on empirical and theoretical evidence specifically about cloud reflectivity, rather than simply making clouds more reflective because the model overall showed more heating than happened in reality. The reason that Kevin C wrote that sometimes those adjustments help the overall model output's fit and sometimes they don't, is precisely because those adjustments are not merely tunings to force the model to fit the past-observed reality.
Even if the modelers do succeed in improving the model's realism in some particular, narrow way, the effect on the model's overall, ultimate projection of temperature might be worse. For example, suppose cloud reflectivity had been modeled as too low, but that incorrect bias toward too much warming was counteracting a bias toward too much cooling in the modeling of volcanic aerosols. If the modelers genuinely improve the modeling of cloud reflectivity but do not realize the too-cool bias in the modeling of volcanic aerosols, then by reducing the warming from clouds they reduce its counterbalance of the overcooling from volcanoes, and the model's overall projection of temperature from all factors becomes worse in the too-cool direction.
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Andy Skuce at 07:26 AM on 31 March 2014Honey, I mitigated climate change
Ranyl provided a link to a site from a Hawaiian power company that has an interesting and somewhat depressing table. About 88% of the electricity on the islands is generated by fossil fuels, mostly diesel, which is a very expensive way to generate electricity. Yet, only 0.1% of the electricity is solar-generated. You would think that with reports that say that PV electricity is becoming as cheap as coal or gas fired electricity in the continental US and Germany, solar electricity in sunny Hawaii, where it displaces expensive diesel electricity, would be a no-brainer. Hawaiian residential electricity prices are $0.37 kW/hr, right up there with the more expensive European prices and three times what they are in the rest of the USA. Why hasn't there been a massive rush to install PV in Hawaii?
These issues are usually more complex than they appear from a quick Googling, so if anybody has any insights into this, I would like to hear them.
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Andy Skuce at 07:08 AM on 31 March 2014Honey, I mitigated climate change
Ari commented in his piece that natural gas replacing coal increases warming in the short ter because of the reduction in aerosols from coal. This observation applies equally to renewables that replace coal, as well. Particulates are a huge health risk, indoors and out, killing millions every year. They will surely be, or should be, reduced regardless of any short-term effect they have on the climate. And coal is not the only villain: the OECD reckons that there are 40,000 deaths per year in France from diesel fumes alone. It's not quite fair to link the climate effects of particulate emissions reductions with natural gas usage.
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Tom Dayton at 05:55 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj, you wrote "Do any of the models actually fit the data or are we just saying that if we look at all the models their dispersion sort of covers a range wide enough that the real data fall within?"
Your question is ill-formed, because you have not specified what "actually" means. No prediction in any branch of science ever is perfect; it is valid (accurate and precise--those terms mean different things) only to some degree. Deciding whether a prediction ("projection" in our case) is sufficiently valid depends on combined probabilities and consequences of the various types of correct and incorrect actions that you could take based on your interpretation of the sufficiency of the prediction/projection.
In this case we are concerned with the projections over periods of 30 years or more (the definition of "climate"). We know that projections over shorter periods are going to be poor, especially when you get down to periods as short as ten years. But we also know that the range of those short-term projections is bound by physics ("boundary conditions"), thereby demarcating the most probable longer term (climate) range of short-term projections. Those squiggly thin orange lines in Figure 2 above are individual runs of models. The models differ from each other by design, most having been built by different people. Usually each model also is run multiple times, varying some factors as a way of sampling the range of their possible behaviors since we are confident only in a particular range of those behaviors. It's similar to running an experiment multiple times to prevent being misled by one particular random set of circumstances. The high and low extents of those squiggly orange lines represent a reasonable estimate of the bounds of the temperature.
Perhaps you are being misled by a belief that if we cannot predict short term temperature we cannot predict long term temperature. That is a common but incorrect belief. See the post "The Difference Between Weather and Climate," and Steve Easterbrook's balloon analogy on his Serendipity site.
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Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj - Climate models predict what the climate will do over the long haul given a particular set of forcings.
Climate models do not predict economic activity (or the GHGs and industrial aerosols produced), they do not predict volcanic eruptions, they do not predict the strength of the solar cycle, and while many of them include ENSO-like variations, they do not predict _when_ those El Nino or La Nina conditions will actually occur.
Various projections (what-if scenarios) have been run for the IPCC reports with reasonable estimates of those forcings variations, but it is entirely noteworthy that the CMIP3 and CMIP5 runs did not include the _particular_ set of variations over the last few years as actually occurred - that would have required precognition. And as per the opening post, when those _actual_ variations are taken into account rather than the before-hand projections, the climate models do indeed give a good reproduction of real climate behavior.
Which means that those models continue to be reasonably accurate representations of the Earths climate, and have not been invalidated in any way whatsoever.
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Tom Dayton at 02:46 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj, climate models are not intended for predicting the forcings (greenhouse gas emissions volcanic emissions, solar energy hitting the Earth, etc.), nor does anyone use them for that. Instead, climate models are intended for, and used for, "predicting" the climate response to one particular "scenario" of forcings. I put "predicting" in quotes, because the model run is not a genuine claim that that climate will come to pass, because there is no claim that that scenario of forcings will come to pass. Instead, the term "projecting" often is used instead of "predicting," to indicate that that climate is predicted to come to pass only if that particular scenario of forcings comes to pass. Those scenarios of forcings are the model "inputs" that other commenters have mentioned in their replies to you.
For each scenario of forcings that someone thinks might come to pass, that person can use those forcings as inputs to climate models to predict the resulting climate. To cover a range of possible scenarios, people run the climate models for each scenario to see the resulting range of possible climates. You can see that, for example, in Figure 4 in the post about Hansen's projections from 1981. You can also see it in the post about Hansen's projections from 1988. To learn about the forcings scenarios being used in the most recent IPCC reports, see the three-post series on the AR5 Representative Concentration Pathways.
To judge how well the climate models predict climate, we must input to those models the actual forcings for a given time period, so that we can then compare the models' predictions to the climate that actually happened in the real world where those particular forcings actually came to pass. That is the topic of the original post at the top of this whole comment stream.
To judge whether climate models will predict the climate in the future whose forcings we do not yet know, we must guess at what the forcing will be. We do that for a range of forcing scenarios. The bottom line is that every single remotely probable scenario of forcings yields predictions of dangerous warming.
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Honey, I mitigated climate change
CBDunkerson - Actually, space based dynamic generation (mirrors, boilers, and generators) has something of a mass advantage over PV, as the mirrors could be exceedingly light mylar or similar materials. It's been less frequently proposed mostly due to the need for maintaining moving parts - you can't just jump in a utility van and apply the wrench. Space based PV might benefit in mass from concentrator mirrors too, depending on whether any need for increased radiator mass would outweigh the reduction in panels.
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CBDunkerson at 02:14 AM on 31 March 2014Honey, I mitigated climate change
Michael Whittemore, either mirrors or PV panels could be directed to multiple ground based sites... though it would be much easier with PV panels because only the microwave emitter would need to be re-aligned rather than all of the mirrors. Also note that mirrors would effectively be creating a giant 'heat ray' from space focused on a small point on the ground, which could be a problem for birds and aircraft. Meanwhile, PV could be transmitted down harmlessly as microwaves over a wider area. Finally, the atmosphere (and clouds) block sunlight much more effectively than they do microwaves... so solar PV panels in space would actually produce more electricity than the same panels on the surface. The mirror approach could gain similar benefits by putting the steam turbines in orbit too, but getting that amount of mass (not to mention the water) into space would be prohibitively expensive.
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Kevin C at 01:07 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
But that's the wrong uncertainty. The uncertainty in the trend arises from the derivation of the temperature series from linearity. The uncertainty we need for that comparison is the uncertainty due to internal variability, which will generally be larger because it also includes differences in trend. There is also doubt as to whether model spread is a good measure of this.
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Honey, I mitigated climate change
Michael Whittemore - I believe that most space-based solar power proposals include using laser or microwave wireless power transmission to Earth; extension cords are sadly not practical with todays technology :) Power density would be considerably higher, given the lack of atmosphere, clouds, or night.
I suspect that using satellites as mirror concentrators would be less cost effective than just larger collection areas on the surface.
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Klapper at 00:03 AM on 31 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@scaddenp #19:
"The models are good at predicting what 30 year trends will be however."
The current HadCRUT4 SAT trend for the last 30 years is 0.17C/decade +/- .05. The CMIP5 ensemble SAT trend for the same period (1984 to 2013 inclusive) is 0.26C/decade, which is outside the 2 sigma range of the empirical data. I checked the CMIP5 ensemble for both 80 to -90 and 90 to -90 (pole to pole) to see if the leaving the very high arctic out would improve, but it makes essentially no difference (0.26 compared to 0.25).
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Michael Whittemore at 23:34 PM on 30 March 2014Honey, I mitigated climate change
CBDunkerson my understanding is that it would take a large amount of panels to be put in space to generate enough energy but with mirrors they could focus on different power plants around the world and not just solar but the land based mirror ones too that generate steam.
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Honey, I mitigated climate change
Ranyl - PV, like any piece of electronics, does have manufacturing waste which must be managed, appropriately recycled, etc. As in the electronics industry, proper monitoring and regulation is necessary. As to coal - damage to watersheds and water supplies, the CO2 and greenhouse effects thereof that are at the center of the climate change discussion, and the particulate and even radioactive release of radon and other elements (with emissions being a continuous output, not just a one time manufacturing cost).
_All_ energy sources, coal, solar, nuclear, etc, have side effects - it's a matter of deciding which effects are more problematic. I would strongly argue in the comparison of solar and coal that the advantages of no carbon emissions _hugely_ gives the balance to solar, and I consider your solar objections more quibbling than anything else.
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michael sweet at 21:47 PM on 30 March 2014Honey, I mitigated climate change
Ranyl,
I quoted from your sources to show that solar did not have the problems you claimed. You respond with more unsupported wild claims You have provided exactly zero quotes to support your wild claims. Your assertions about solar are false. Your claim that Hawaii uses extensive geothermal must be supported by a cite. I have seen extensive data supporting the claim that Hawaii has reduced its fossil fuel use with solar. What do you thnk happens to fossiil fuel use when wind generates more energy? Do consumers use more power? Be serious, of course fossil fuel use goes down. You appear to claim that all energy use must be curtailed. That will never happen. You must provide an alternate scenerio for people to live.
You are ranting and sloganeering. Provide more citations that support your wild claims and less assertions from ignorance.
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ranyl at 21:17 PM on 30 March 2014Honey, I mitigated climate change
"Ranyl, you may want to take a look at Hawaii. It has greatly decreased fossil fuel usage by adopting renewable power. Your belief that this is impossible is thus simply wrong."
Who said this was a beleif, and I'm not Richard York, he is and he worked out, he didn't just beleive it.
And Hawaii has extensive Geothermal which York isn't discussing, he is discussing PV, wind etc...and of relevance to this article and future food as climate change puts the strain on, "In May we signed a power purchase agreement with Hu Honua Bioenergy for up to 21.5 MW of firm renewable energy fueled by locally grown and produced biomass on the Big Island. Pending Public Utilities Commission approval, plans call for bringing the power plant online by the end of 2013", that is lot of MW to grow., are people actually starving in our world why we grow plants to serve of power addiction, is that really happening??? and advocated by environmentalists?
And I see all good now because toxic PV is cheap and easy to do I see, no ownder I passed a several acrePV array in yesterday on prime farmland, wonder that does to soil carbon, the ecosystem in the soil and dispalced food crop?How much land would be needed to supply a major city and industry from PV and what storage would be needed, or are talking a global power sharing grid?
Any environmental impacts of common storage devices? Batteries Lithium mining, trasnport, toxic prodcution, toxic waste, etc,etc, what biodiverstiy crisis?
And the grid any additionals needed to that to cope with PV?
Is the answer to actual admit that there si no clean power production, that we already need to remove ~100ppm from the atmosphere to get ot 350ppm (the 50% of emissions stored in the sinks will be released as the atmospheric CO2 conc falls accordign thse guys;
Atmospheric carbon dioxide removal: long-term consequences and commitment, Long Cao and Ken Caldeira, Environ. Res. Lett. 5 (2010)
And these guys estimate if we stopped all CO2 tomorrow only drops very slowy at best 0.2ppm/y-1, so take the earth 250years to get 350ppm without the re-release from the sinks.How difficult is it to recover from dangerous levels of global warming? J A Lowe1, C Huntingford2, S C B Raper3, C D Jones4, S K Liddicoat4 and L K Gohar1, Environ. Res. Lett. 4 (2009)
When CO2 was 350ppm last the wordl was 3-5C hotter and 20-25m sea level rise different and the cliamtic zones and oceanic zones where quite different, and severe weather in terms of rain amounts and wind dissipation must have been quite something with all that extra heat and energy about.We are admidst a rapid mass extinction, very rapid loss of biodiversity and all due to human practices of consumption, overexploitation, fertilization, land use change and introducign am array of toxic substances.
And here we are discussing using an technology with a very high energy input to produce, multiple toxic waste issues at all stages including recycling, that is totally dependent on fossil fuels to make at presetnt and user of land now in more and more places.
And now it si becoming cheap and open to mass manufacture and can be put into anything so now totally open to mass ocerexploitation so its all ok.
Therefore coal is awful and if we continue with that then the upshot civilization chaos and that is never pretty.
Solar PV is another enrgy source, that isn't as bad, but pretty awful and if waste leaks or factory blown up very bad as substances used in manufacture so toxic and GHG effects so high, imagine if all the NF3 escaped.
Therefore the question here is to either power down or use PV and continue the harm and probaly increase it as the full extent of putting waste into the environment emerges due to bioaccumulation and concentrations of these substances, and how carbon does it cost when you disrupt an ecosystem?
Choice Power down or toxic waste?
And lastly to get to 350ppm means we need to be carbonnegative and every ounce of carbon has to be recovered so where si all this carbon to make all these PV's coming from.
And as many LCA (lots very biased) give ~6-8years for PV, that measn for 1 year production you have make 6 to 8 years worth, which of course takes at present all number of PV's of fossil fuels to make an PV factory from PV alone, spo that is a lot, 36 to 64 years of equivalent emissions to set up, and that isn't including NF3 or Hydroflourides or the effects of the toxic wsaste on the environmental carbon fluxes.
Power down is safe, costs no GHG, produces no waste and is actually easy to do.
And yes I am writing on a CPU which is toxic waste, and yes we do need to do somethign about that to.
We are between a very hard rock and a very hard place, 35ppm is a miracle away, needs stoppign all fossil fuel use asap and not using other powwr generation that has large environmental imapcts especailly in big scale overexploitation. And we haven't even started on where the silicon coms from, the rare earths, the aluminium, the solder, the lead, the glass, the transportation, making the factories, all the chemical used, and so and so on...
Therefore the choice is powerdown nice and safe in all respects or not and keep on harming just not quite severely as coal?
Moderator Response:[RH] Hot-linked URL.
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CBDunkerson at 19:19 PM on 30 March 2014Honey, I mitigated climate change
Michael Whittemore, once you get to the point of launching things into orbit it actually makes more sense to put solar PV panels in space to collect sunlight 100% of the time and beam the power down to rectifying antennas on the surface.
That said, I think what I call 'solar overkill' may be the most likely / cost effective scenario. There are technologies in place which can gather solar PV energy from transparent windows, roofing shingles, building siding, sidewalks, driveways, and even clothing. If the cost of solar PV continues to plummet, we may see it being incorporated into anything and everything... resulting in most buildings generating more electricity than they use and thus always sufficient 'extra' power to transfer to sites which are currently dark.
Ranyl, you may want to take a look at Hawaii. It has greatly decreased fossil fuel usage by adopting renewable power. Your belief that this is impossible is thus simply wrong.
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ranyl at 18:44 PM on 30 March 2014Honey, I mitigated climate change
"If this is the best you can do the solar industry is ready to go all out. All large electronic firms in China should be carefully watched. Your claims that solar (and wind) cannot be environmentally produced do not stand up to a review of your own citations."
Firstly yes PV is better than coal, but we need to stop using coal asap as I said, no brainer just like the article say, but not sure why you use that as proof of PV being good for the environment, PV are just another power generation technology with major environmental impacts, like a machine gun we kill loads of people (coal) compared to a hand gun, a hand gun (PV) still kills.
Therefore nothing you have said is saying making PV's is of environmental benefit, we have hope they make clean factories, we have to hope, but how do they treat the waste and what do they do with it? How do they make in benign exactly?
LINK
Lots of waste left behind here from a clean factory.
https://alumni.stanford.edu/get/page/magazine/article/?article_id=30242
Another statement on some of the issues and again we hope factories will clean up...and how many factories are in China and growing
http://www.nrel.gov/docs/fy12osti/53938.pdf“Non-hydro renewable sources have a positive coefficient, indicating that renewables tend to simply be added to the energy mix without displacing fossil fuels.”
“The failure of non-fossil energy sources to displace fossil ones is probably in part attributable to the established energy system where there is a lock-in to using fossil fuels as the base energy source because of their long-standing prevalence and existing infrastructure and to the political and economic power of the fossil-fuel industry.”
Richard York1 Do alternative energy sources displace fossil fuels?
Nature Climate Change Volume: 2, Pages: 441–443, 2012They haven't even displaced any coal yet either, so all just additional harm.
PV is a dirty, high enery environmentally destrcutive technology, better than coal but still in no way an environmental benefit at all to no one or anything.
Moderator Response:[RH] Hot-linked URL.
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Kevin C at 18:26 PM on 30 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj asks an interesting question:
Can you tell me how many adjustable parameters there are in each of these models?
The question doesn't really apply, because climate models are not statistial models. However from the point of view of fitting global mean temperature, I think the most meaningful answer would be 1 - because we align the baselines to compare the models.
Climate models are optimised by improving the physics. In some cases the physics cannot be modelled at a sufficiently fine scale, and in these cases parameters are used. However those parameters are not, and cannot be, optimised to reproduce global mean temperature - they are optimised to produce the right local behaviour. The global impact of those optimisations is an emergent property, and may improve or degrade the fit.
Of course we then get into the tuning myth, which was explored in another recent discussion - from memory I think we found that it arose in part from not counting the number of independant models correctly, and has changed signs between CMIP3 and 5.
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scaddenp at 17:02 PM on 30 March 2014Global warming not slowing - it's speeding up
There may be another source of confusion - the OHC shown is change in OHC compared to 1955-2006 baseline period not the absolute OHC.
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scaddenp at 16:57 PM on 30 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Martin, model are not skillful at decadal level predictions. There is a very good reason why climate is defined as 30 year means. Besides ENSO and solar variation, there are modes of internal variability on decadal scales. The models are good at predicting what 30 year trends will be however. The AR5 report indicates the ensemble range. I would say the uncertainty band is at least as large as this. Emissions and aerosols are under our control so model can only deal with scenarios for these.
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scaddenp at 16:17 PM on 30 March 2014Global warming not slowing - it's speeding up
Sorry, you are saying T = 3/2 kT?? that doesnt make sense. The temperature change from a given no. of joules is divide by volume of water and volumetric heat capacity (4.15MJ/m3 approximately). OHC is actually calculated from the deltaT by same formula.
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Michael Whittemore at 15:10 PM on 30 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj read the post again. Models can't predict elninos/laninas, solar forcing or volcanic eruptions. No one can predict them. This post is just showing that when you take out these effects on the climate system, the models are spot on.
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Rob Painting at 15:07 PM on 30 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
The output of the climate models depend on the input. The CMIP5 climate models were fed input, a net climate forcing, that does not appear to have occurred. When fed the updated input, the multi-model mean and observed temperatures are well-matched.
None of this has anything to do with adjusting how the models themselves are run.
As for hindcasts, similar problems remain. What net forcing was the climate system itself actually responding to back then? Earlier periods are less well contrained by observations, so we can only make an educated best guess.
And one last thing, the thrust of your comment constitutes a breach of the comments policy namely; slogan-chanting and accusations of scientific malfeasance. Further breaches will likely attract moderation.
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BruceWilliams at 14:58 PM on 30 March 2014Does the global warming 'pause' mean what you think it means?
Tom Curtis @ 27
Although not directly coupled, would it be fair to say that the OHC must eventually follow the SST?
I ask because if not then the heat transfer characteristics surface to bottom must be different than from bottom to top, or there is a heat/cooling action going on at the bottom?
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BruceWilliams at 14:22 PM on 30 March 2014Global warming not slowing - it's speeding up
Concerning post #23 scaddenp at 08:25 AM on 14 March, 2014
According to the graph presented, the energy content of the southern hemisphere went from 4.5e22 J to 9e22 J in about 5 years. Since temperature is simply 3/2 kT would this not indicate that the temperature of the southern hemisphere ocean area has doubled in the last 5 years?
Note: k = Boltzman constant
T = Temperature (average)
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Matzdj10109 at 12:35 PM on 30 March 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Please help me understand. Do any of the models actually fit the data or are we just saying that if we look at all the models their dispersion sort of covers a range wide enough that the real data fall within?
Can you tell me how many adjustable parameters there are in each of these models? (-snip-).
I understand that at any given time, each model is fit to the historical data and the adjustable parameters are calculated. If it fits with a good correlation, that's great, but the test of the model is whether future data fits what the model predicts. It's not good science to take the future data, refit the adjustable parameters and then report that the model fits. That usually indicates that there probably is some important physical issue that is either not in the model or not being considered correctly - maybe something like cloud formation?
If you want to put a parameter into the model that does some cooling if a volcano explodes or a La Niña happens, that's ok, but only if you do it in a way that incorporates it without using the result to readjust the fit. (-snip-).
If someone can take just one model and show how it has predicted the 10 years after the parameters were fit, I would be very appreciative.
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Michael Whittemore at 11:18 AM on 30 March 2014Honey, I mitigated climate change
Regarding solar farms and molten salt farms, you would think governments would put mirrors in space to keep these powers plants working 24/7
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scaddenp at 10:51 AM on 30 March 20142014 SkS Weekly News Roundup #13A
"How certain" is actually what is relevant rather than philosphical arguments about what is knowable and what is not. Policy makers have to make decisions all the time in the face of uncertainty. It is possible that some new theory will explain all our observations what implying that we need to act on our emissions, but extremely unlikely. "The race is not always to the fastest, nor the fight to the strongest, - but that's the way to bet". Trying to use the lack of certainty as an excuse for inaction is extremely poor policy. Uncertainty cuts both ways.
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Tom Dayton at 10:41 AM on 30 March 20142014 SkS Weekly News Roundup #13A
Tom Curtis, not even mathematics is absolutely certain, because humans create the mathematical descriptions. Else all mathematical "proofs" would be unerringly correct forevermore, at the first moment that any one human was "certain" of their correctness.
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Tom Curtis at 09:51 AM on 30 March 20142014 SkS Weekly News Roundup #13A
Stephen Baines @16, thanks for a well written and clear exposition. It misses, however, some nuances. Specifically, and first, when we practice science as an endeavour, we continue to use the "certain" parts of science as an instrument (often literally) in our inquiry about the uncertain parts. If we use a microscope, we relly on the near absolute certainty of aspects of optics in doing so. If we examine the operation of climates, we relly on the certainty of the Navier-Stokes equations, of the laws of thermodynamics, Galilein mechcanics and Newtonian dynamics as approximations to their relativitistic counter parts at low velocities, the composition of the atmosphere, the radiative spectrums of the components of the atmosphere, the response to atmospheres to Newtonian gravity (as an approximation to their behaviour under General Relativity) and so on. We rely on the certainty of hundreds of physical laws in the instruments we use to probe the climate and its components.
Further, of necessity we always focus our enquiries such that what is uncertain is a small part of the operation, and what is certain is large. So far as is possible, we always make sure there is only one, or very few dependant variables. Where we not to do so, no enquiry could reduce confusion. Consequently, even as an endeavour, that which is certain in science far exceeds that which is uncertain.
What is true, almost tautologically, is that which is subject to active enquiry is not yet certain. Science always enquires on the edge of ignorance; from which we cannot conclude that 'nearly all of science is ignorance'.
The second point is that no part of science (except mathematics) is absolutely certain. Even the theory that there is an external world (ie, that we are not "brains in vats") could, in principle be overthrown by continuing observation. But the possibility of this, or that the Earth is flat, or (and here with space I would list the majority of scientific knowledge), is so small that without the occurence of evidence that calls it into question, the possibility of error on these points can be neglected in practise.
There is an unfortunate tendency among some scientists and commetators on science to notice the first poin in the above paragraph, and to think that it seriously calls into question the second. Of course, no scientist actually puts that radical skepticism into practise. If they were to do so, they would never determine any result, out of complete mistrust of their instruments.
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